Other Crops
Domesticating plants to grow as crops can turn out to be a double-edged scythe.

On one hand, selecting specific desirable traits, such as high yields, can increase crop productivity. But other important traits, like resistance to pests, can be lost. That can make crops vulnerable to different stresses, such as diseases and pests, or the effects of climate change.

To reduce these vulnerabilities, researchers often turn to the wild relatives of crops. These wild relatives continue to evolve in nature, often under adverse conditions. They possess several useful genes for desirable traits. These traits include high levels of resistance to diseases and tolerance to environmental stresses.

In a new study, scientists report significant strides in transferring disease- and stress-resistance traits from wild relatives of several legumes to their domesticated varieties. This research was conducted at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Patancheru, India.

Legumes, such as chickpea, pigeonpea, and groundnut, are among the few crops that grow well in the scant rainfall and marginal soils of the semi-arid tropics. But they are facing significant challenges, says Shivali Sharma, lead author.

“Legume crops are hit hard by diseases, insect-pests, drought, heat stress, and salinity,” says Sharma. “Also, semi-arid regions are highly vulnerable to climate change.” These factors limit legume crops.

There are several wild relatives of these crops that are resistant to pests and diseases. “There is an urgent need to find and introduce these useful genes from wild relatives into crop cultivars,” says Sharma. That would improve the resilience of domestic legume varieties and sustain agriculture in these regions.

It can be highly challenging – and often impossible – to directly breed domesticated crops with their wild relatives. For example, of the eight wild annual species of chickpea, only one is readily crossable with cultivated chickpea and yields fertile offspring.

Similarly, wild varieties of groundnut are resistant to fungal infections. But direct crossing of wild and domesticated groundnut is challenging because of differences in how the DNA in their cells is packaged. Additionally, these species do not cross well with cultivars.

Most wild varieties of groundnut are diploid: their DNA is organized in two sets of chromosomes per cell, much like in humans. During reproduction, one set comes from the male parent and the other set from the female parent.

Domesticated groundnut plants, on the other hand, are tetraploid. Their cells contain four sets of chromosomes. The sets of chromosomes in each cell, called ploidy, makes it difficult to directly interbreed wild and domestic varieties of groundnut.

“It takes a lot of time and resources to overcome challenges like these,” says Sharma. “That often makes breeders reluctant to directly use wild species in breeding programs.”

Pre-breeding programs, such as the one at ICRISAT, invest their time and skill in the wild crop relatives. Sharma and her colleagues bred wild groundnut varieties whose cells have four sets of chromosomes. Then they identified which of these tetraploid wild varieties were also resistant to fungal infections. These were then crossed with cultivated groundnut varieties to develop new breeding lines with good resistance and yields. Plant breeders can now directly cross these fungal-resistant lines with domesticated groundnut to create new varieties.

“Crop wild relatives are the reservoir of many useful genes and traits,” says Sharma. “It is our responsibility to use this hidden treasure for future generations.”

It’s especially important in the context of legumes because they provide a bevy of benefits. For instance, bacteria in their root nodules pull in valuable atmospheric nitrogen. That increases soil fertility and reduces the need for fertilizers.

Legumes are also vital for food security in the semi-arid tropics and other parts of the world. They are an important source of protein and micronutrients. Combined with cereals, they are a sustaining diet for people across the world.

And “pre-breeding programs are the first step to improve the nutrition and resilience of modern legume varieties,” says Sharma.

Read more about this research in Crop Science.
Crowds, new ideas, research and equipment – something’s going on with cover crops in Ontario.
Though often abused and neglected, mixed forage stands can respond to fertilization. Still, some growers are hesitant to apply fertilizer to meet fertility needs, perhaps because forage yields tend to decline over time or because lack of spring rainfall can limit yield responses.
Just like you inoculate legume seeds with a rhizobial inoculant, one day you might inoculate canola seeds with a plant-growth-promoting fungus. Greenhouse experiments in Alberta are showing that a fungus called Piriformospora indica can boost canola performance, providing benefits like increased yields, reduced fertilizer needs, and increased tolerance to cold and drought. Now the research team is testing this promising inoculant in the field.

Piriformospora indica was discovered relatively recently in northwest India, and since then has been found in other parts of the world,” notes Janusz Zwiazek, a professor of plant physiology at the University of Alberta, who is leading the research. Since Piriformospora indica’s discovery about two decades ago, researchers have been learning more and more about this interesting fungus. Zwiazek expects it will likely be classified as a type of mycorrhizal fungi.

He explains that Mycorrhizal fungi are a group of fungi that colonize plant roots, forming mutually beneficial relationships with their hosts. “Mycorrhizal fungi are very common. Probably more than 90 per cent of plant species are associated with mycorrhizal fungi in nature. Especially in soils that are poor in nutrients such as phosphorus and nitrogen, these fungi can mobilize these nutrients in the soil and make them available to plants. Mycorrhizal fungi can also protect plants against different environmental stresses such as drought, pathogens, and so on,” says Zwiazek.

“But the exception is the family of Brassicaceae, the cabbage family of plants, to which canola belongs. Cabbage family plants typically don’t form mycorrhizal associations. So they don’t have the added benefit that many other plants receive from having these helpful fungi that can do so much good.”

Luckily for canola growers, Piriformospora indica is a bit different from the average mycorrhizal fungus in a couple of ways.

“Researchers have discovered that Piriformospora indica is capable of forming associations with the roots of a number of cabbage family species,” notes Zwiazek.

Also, most mycorrhizal fungi have to be cultured in a plant host, but Piriformospora indica can be grown in a pure culture without a plant host, so it is easier to grow for commercial production of inoculants. And previous research has shown that Piriformospora indica has the ability to provide multiple benefits to host plant species, such as improving nutrient uptake, increasing stress tolerance, improving disease resistance, and enhancing plant performance.

With all those things going for Piriformospora indica, Zwiazek was keen to see how it might work with canola.

The first phase of the project was done in growth rooms where all the environmental conditions, such as temperature, light and moisture, were strictly controlled. The experiments were done under sterile conditions to exclude the possible effects of any other microbes.

“We inoculated canola plants with a fungal culture of Piriformospora indica, and we studied the effects on plant growth under different environmental conditions, which we controlled in the growth rooms,” he says. Zwiazek’s team evaluated the effects of such things as temperature stress, low nitrogen and phosphorus levels, drought and flooding stress, and salinity stress on canola growth characteristics and yields, with and without the fungus.

The biggest challenge in the project’s first phase was to develop a practical way to inoculate canola plants with the living fungus. Zwiazek explains, “In many cases, [commercial] mycorrhizal associations and mycorrhizal technology have failed because it is very difficult to inoculate the plants on a large scale, to maintain the inoculum alive long enough and develop the conditions which could be used on a commercial level and applied in practice.”

After testing various Piriformospora indica inocula and procedures, the project team has developed an innovative inoculum and protocol that are practical for applying the fungus to seeds in commercial operations. They are currently applying for a patent for this technology.

The project’s first phase is largely completed, and the results are very promising.

“The most important findings are that the fungus can colonize canola plants quite easily and quite effectively, and it can be quite effective in increasing the growth and yield of canola, especially under lower phosphorus levels,” says Zwiazek. “Also, the fungus makes the plants more resistant to low soil temperatures and low air temperatures, and to drought stress conditions.”

Now the next step is to see how well Piriformospora indica works under field conditions. So in 2016 the project team started testing the inoculant in field trials.

In these trials, Zwiazek’s team will be looking at the effects of different soil amendments (including different soil organic matter and growth-promoting bacteria) on canola growth and yield, with and without the inoculant. As well, they are doing some tests in collaboration with Mary Ruth McDonald from the University of Guelph and Habibur Rahman from the University of Alberta to see how the fungus affects the canola plant’s ability to resist clubroot and possibly other canola pathogens.

“The results of the greenhouse studies are very exciting. But everything has to be really tested in the field – this is the ultimate test. Hopefully in two or three years we’ll have a pretty good idea of how the fungus performs under field conditions, and how much farmers can actually benefit from it.”

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Funders for this research include the Agriculture Funding Consortium (AFC), Alberta and Saskatchewan canola producer groups, Alberta Innovates – Bio Solutions, and Western Grains Research Foundation.
Most eastern Canadian producers have considered whether tile drainage is right for their operations. According to Harold Rudy, executive officer of research and business development for the Ontario Soil and Crop Improvement Association (OSCIA), more than 50 per cent of the agricultural land in southern Ontario is tile drained. In many areas of the province, tile drainage facilitates timely field operations and helps decrease the risk of crop damage during heavy rainfall events.
Tree-based intercropping – growing trees together with crops – is a historical agricultural practice. These days primarily smallholder farmers use it in tropical systems, but researchers are focused on potential applications in the temperate soils of southern Ontario and Quebec.
Winter wheat
The wheat crop continues to grow rapidly in the cool moist conditions and is 5-10 days ahead of normal in general. Following up on last week’s report, by the time sprayers are able to be back in the field, the weed stage and competition from the crop canopy will likely negate herbicide use in most situations.

These weather conditions favour disease growth and although current disease levels remain low in most fields this can change quickly. Septoria leaf spot and powdery mildew are the most common diseases present currently and primarily still situated in the lower canopy. Last week leaf rust was found in Bruce County as well as wheat spindle streak mosaic virus was confirmed in Essex County. With the rapid growth of the crop and favourable weather conditions, it is important to continue scouting to determine if fungal disease infection is progressing up the plant (especially on susceptible varieties) and if a fungicide application is needed. With the rapid growth of the crop, scouting for effectively timing fungicide applications is critical. Crop growth stage, climatic conditions, variety susceptibility, presence of or anticipation of disease are all considerations that go into the decision if and whether a fungicide application is needed.

Stripe rust at very low levels was found in one field in Essex County last week on a susceptible variety. The infection was mid canopy which considering the recent storm systems, would suggest spore movement into Ontario from the Midwest US and not overwintering. Unfortunately, weather conditions favor further stripe rust development and spread. As was seen last year, there are large differences in variety susceptibility to the disease. Check with your seed supplier and the Ontario OCCC performance trials for specific variety ratings. All wheat growers should be scouting for stripe rust and based on last years’ experience, a preventative fungicide applied to susceptible varieties was beneficial and a good integrated wheat disease management strategy. Fields planted with susceptible varieties should spray while those with tolerant or resistant varieties need to regularly assess fields from now until heading to assess stripe rust risk.

Corn
Very little progress has been made in corn planting as wet weather continues to delay fieldwork. But the consequences of getting on fields too quickly can be significant. Everyone is fixated on the importance of early planting date. What is forgotten is the statement “given field conditions that are fit for planting” which should precede any mention of early planting date. The fitness of the soil for planting is always the most important consideration, and then planting date.

Weather is the biggest factor and we can’t control it but we can to some degree manage around it. If you compromise the crop right from the start, its ability to buffer against other weather and stress extremes will be compromised. Plant by soil conditions, not the calendar.

If there is only a small window to plant, it's best to plant first and apply nitrogen afterwards provided you have the means to do so.

When planters start rolling, some may try and get ahead by speeding up planting. Unless your planter is setup for it and the field conditions can take it, you are likely not helping yourself. Cutting corners on planting pays no dividends. The continued cool forecast means we have not lost much heat with the seed still in the bag. Last week Wednesday to yesterday we achieved only 10-20 CHU across the province. It takes 180 CHUs from planning to emergence.

Soybeans
While a few acres of beans have been seeded, field conditions have not allowed for large scale seeding. Early planting is less critical to yield for soybeans than corn. Soybeans planted in mid-May often have the highest yield potential. Something to consider while waiting to get back in the field is seed size. Soybean seed size tends to be large this year and this has implications for planting equipment. Ensure that your equipment is set up to deliver whole seed effectively to the ground. A split seed will not survive. Soybean seed supply is tight in many zones so ensure you have your needs confirmed. Last year’s weather hurt seed quality resulting in a lower volume of high quality seed being available. Trying to switch corn acres to beans as the planting season condenses may be difficult.
Field scouting is an essential part of integrated pest management, used to examine all aspects of crop production to achieve optimum yield. Scouting is the process of monitoring crop development in each of your fields to evaluate crop concerns and economic risks from potential pests and diseases.
The relationship between bees and canola is strong, just ask any honey producer. But what benefits do canola growers receive from those colonies parked at the corner of a field? New research in Alberta is delving in to that sweet subject.
Research shows you can get those healthy omega-3 fatty acids not only from eating ground flaxseed and flaxseed oil, but also from the eggs, meat and milk of flaxseed-fed poultry, swine and cattle. Perhaps, then, it’s no surprise the Canadian flax industry is working to enhance and expand omega-3 opportunities with flaxseed feed and focusing on how flaxseed feed’s many healthy attributes can benefit animals, livestock producers and feed processors while expanding the flaxseed feed market for growers.
I call them my second herd,” says Brian Slenders, an alfalfa and canola seed and livestock producer near Scandia, Alta., and president of the Alfalfa Seed Commission of Alberta.
Diversified crop rotations are an important component of western Canadian cropping systems. Although crops like wheat and canola are the largest acreage crops, adding special crops into the rotation helps manage weed, disease and insect pest problems and potential resistance issues, improves soil health and maximizes profitability. However, determining which crop fits best in the cropping sequence remains a big question.
A recently discovered mycorrhizal fungus, Pirifomospora indica, holds promise for improving canola production. Ajit Verma, a professor in Jawaharlal Nehru University’s School of Life Sciences in New Delhi, discovered the fungus on orchid plants in the Thar Desert in Rajasthan, India. Since the discovery of P. indica, scientists around the world have been working to understand the benefits of the fungus.  
Hulless barley, pioneered at Virginia Tech, adds a new dimension to this grain. With a higher starch content and better proteins compared to hulled barley, it’s also a good choice for double-cropping with soybeans since it ripens earlier. | READ MORE
Drought-tolerant wheat may exist on some mountaintop in Nepal, but in the laboratories of wheat breeders, it is truly elusive. It’s on the priority list, but don’t look for significant changes coming any faster than climate change.
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